Incorporation of Variable-Speed Pumping in Multiobjective Genetic Algorithm Optimization of the Design of Water Transmission Systems

Abstract

Authors may post the final draft of their work on open, unrestricted Internet sites or deposit it in an institutional repository when the draft contains a link to the bibliographic record of the published version in the ASCE Civil Engineering Database. "Final draft" means the version submitted to ASCE after peer review and prior to copyediting or other ASCE production activities; it does not include the copyedited version, the page proof, or a PDF of the published version. that the use of variable-speed pumping leads to significant savings in both total cost and GHG emissions from WTSs for the case study considered.

Lost in Optimisation of Water Distribution Systems? A Literature Review of System Design

“…Even though there is a significant tradeoff between economic and environmental objectives (i.e., GHG emissions decrease with the increasing costs and vice versa), GHG emissions can be considerably reduced by a reasonable increase in the costs [71,72]. Additional results indicate that the price of carbon has no effect on the tradeoff [77], whereas the discount rates do [72], the use of variable speed pumps (VSPs) (rather than fixed speed pumps (FSPs)) leads to significant savings in both total costs and GHG emissions [74].…”

“…Additionally, the pump maintenance cost (see, for example, [61,62,121]) as well as the pump replacement and refurbishment cost [71,72,77] were accounted for. More recently, GHG emission cost or GHG emissions due to the electricity that is consumed by pumps [71][72][73][74][75][76][77] were introduced as an environmental objective. Similar to the pump operating cost, a PVA can be used for the pump maintenance, replacement and refurbishment costs, as well as GHG emissions/cost.…”

“…A multi-objective optimisation approach was possibly first applied in the late 1990s (Figure 1), maximising the network benefit on one hand and minimising the system cost (of network rehabilitation) on the other hand [63]. In studies of newly designed WDSs, in addition to the economic measure, the other objectives considered were the pressure deficit [30,62,[64][65][66][67] or excess [68,69] at network nodes, the penalty cost for violating the pressure constraint [70], greenhouse gas (GHG) emissions [71][72][73][74][75][76] or emission cost [77], water discolouration risk [68] and water quality [78]. A multiobjective optimisation approach is considered "very appealing for engineers as it provides a tool to investigate interesting trade-offs", for example, a marginal pressure deficit can be outweighed by a considerable cost reduction [67].…”

Comparison of Pumping Regimes for Water Distribution Systems to Minimize Cost and Greenhouse Gases

“…Objectives of pumping electricity cost and GHG emissions are considered separately and the characteristics of the optimal operating strategies for the objectives are compared. Multi-objective optimization of cost and GHG emissions for WDSs has been extensively covered in Wu et al (2010a); Wu et al (2010b); Wu et al (2011); Stokes et al (2012b); Stokes et al (2012c); Wu et al (2012a); Wu et al (2012b); Wu et al, (2013);and Stokes et al (2014). This research is different in that it considers the effect of the different pump operating regimes on each objective individually.…”

Effect of Storage Tank Size on the Minimization of Water Distribution System Cost and Greenhouse Gas Emissions While Considering Time-Dependent Emissions Factors

“…as decision variables in order to find solutions of minimized cost and GHG emissions (Basupi 48 et al 2013;Basupi et al 2014;Dandy et al 2006;Du et al 2013;Herstein et al 2011;49 Herstein and Filion 2011; Herstein et al 2009;Kang and Lansey 2012;MacLeod and Filion 50 2011;Marchi et al 2014;Roshani et al 2012;Wu et al 2010a;Wu et al 2012a;Wu et al 51 2013; Wu et al 2010b;Wu et al 2012b). Both pipe size and pump type are important factors 52 to consider, as they not only explicitly affect the cost and GHG emissions associated with a 53 WDS's design, but also affect the hydraulic performance of a system, affecting pumping 54 electrical energy requirements and therefore the cost and GHG emissions associated with the 55 pumping operation of a WDS (Dandy et al 2006;Herstein et al 2011;Herstein et al 2009;56 Roshani et al 2012;Wu et al 2010a;Wu et al 2012a;Wu et al 2013;Wu et al 2010b;Wu 57 et al 2012b).…”